Image Source: Pexels
 

An Introduction
 

The 26 largest capitalized semiconductor stocks in the 6 segments of the sector, as outlined below, were UP 45% in 2025 after a modest 5% increase in 2024. This article highlights the performances of each of the 6 AI sub-segment portfolios and that of their constituents in 2025.
 

The Sub-segment Portfolios In Our Model AI Semiconductor Portfolio
 

The first 4 of the 6 sub-portfolios consists of those categories that account for the 4 specific steps in the manufacturing of semiconductors, namely:

1. The design of complex semiconductor chips using sophisticated electronic design automation (EDA) software, i.e. Our Model Pure-Play EDA Software Chip Design Stocks Portfolio;
2. The supply of equipment and material necessary to build and operate a semiconductor foundry, i.e., Our Model  Pure-Play Semiconductor Supplier Stocks Portfolio;
3. The foundries that fabricate the chips based on the designs provided by other semiconductor companies, i.e. Our Model Pure-Play Semiconductor Foundry Stocks Portfolio; and 
4. The companies that assemble chips into finished semiconductor components, test for defects, and provide the specialized packaging necessary for shipping the chips around the world, i.e., Our Model Pure-Play Outsourced Semiconductor Assembly & Test Stocks Portfolio.

The other two categories are those major companies that:

1. Design and sell hardware devices and semiconductor chips themselves while outsourcing their fabrication (i.e., are fabless) to a specialized manufacturer; i.e., Our Model Pure-Play Fabless Semiconductor Stocks Portfolio; and
2. Do everything themselves in-house to control the entire production process from beginning to end, i.e., Our  Model  Integrated Device Manufacturer Stocks Portfolio.

The Performance In 2025 Of Each Sub-segment Portfolio
 

5 of the 6 portfolios advanced in 2025 with only our model Pure-Play EDA Software Chip Design Stocks Portfolio declining fractionally (DOWN 0.4%). The average increase of the 6 portfolios was 45.3% and below are their performances, in descending order, along with that of their constituents:

1. Our Model Pure-Play Semiconductor Supplier Stocks Portfolio: UP 74.1% in 2025
   • Constituent Returns:
     • Lam Research (LRCX): + 137.0%; KLAC Corp. (KLAC): +92.8%; Applied Materials (AMAT): +58.0%; ASML Holding (ASML): +54.4%
2. Our Model Pure-Play Semiconductor Foundry Stocks Portfolio: UP 55.5% in 2025
   • Constituent Returns: 
     • Tower Semiconductor (TSEM): +128.0%; Taiwan Semiconductor (TSM): +53.9%; United Microelectronics (UMC): +21.1%; GlobalFoundries (GFS): DOWN 18.6%
3. Our Model Pure-Play Outsourced Semiconductor Assembly & Test Stocks Portfolio: UP 55.4% in 2025
   • Constituent Returns: 
     • ASE Technology (ASX): +59.9%; Amkor Technology (AMKR): +53.7%
4. Our Model Pure-Play Fabless Semiconductor Stocks Portfolio: UP 42.2% in 2025
   • Constituent Returns: 
     • Advanced Micro Devices (AMD): +77.9%; Monolithic Power (MPWR): +55.8%; Broadcom (AVGO): +49.3%; Nvidia  (NVDA): +39.0%; Qualcomm (QCOM): +11.3%; Marvell (MRVL): DOWN 23.1%
5. Our Model Integrated Device Manufacturer (IDM) Stocks Portfolio: UP 35.2% 
   • Constituent Returns:
     • Micron Technology (MU):+239.1%; Intel (INTC): +84.0%; Infineon Technologies (IFNNY): +35.6%; Analog Devices (ADI): +27.7%; Microchip Technology (MCHP): +11.1%; NXP (NXPI): +4.4%; STMicroelectronics (STM): +4.1%; Texas Instruments  (TXN): DOWN 7.5%
6. Our Model Pure-Play EDA Software Chip Design Stocks Portfolio: DOWN 0.4% in 2025
   • Constituent Returns: 
     • Cadence Design Systems (CDNS): +4.0%; Synopsys (SNPS): DOWN 3.2%
        

Summary
 

The 6 sub-segment portfolios in our model AI Semiconductor Stocks Portfolio were UP 45.3%, on average, in 2025, while the Nasdaq (QQQ) was only UP 20.2%.

Addendum
 

The Portfolio is not tradable but if you are interested in investing in this sector check out the VanEck Semiconductor ETF (SMH) which has 26 holdings (almost identical to our model AI Semiconductor Stocks Portfolio) and it was UP 48.7% in 2025.

More By This Author:

AI Semiconductor Stocks Portfolio Was Up 45% In 2025 - Take A Look
Our Model AI Hardware Semiconductor Stocks Portfolio Is The Backbone Of The AI Revolution - Take A Look
What Bubble? All 6 AI Semiconductor Stock Categories Were Up Last Week